Air Source Heat Pumps

richardc1983

Cardew wrote: »

I think you missed Steve's irony!!!

and perhaps mine about a water to air ASHP - or should that be WSHP!

You will have to explain what you mean, im not good at getting forum tone!

richardc1983

stevehead wrote: »

it says so on the net.
.

I read it back was it this bit i missed?

stevehead

richardc1983 wrote: »

you see your unit heat output is double the cooling output!.

Yeah, it is... what do you make of that Rich? Why not the same for both heat/cool?

richardc1983

I dunno really, clearly the heating side of things is one of the benefits of the hyper inverter as apposed to mitsis standard inverter units.

You pay more for the hyper inverter than their standard one, perhaps for that reason, you size for a 2.0kw cooling, however in the winter when temps drop to below freezing your going to have plenty of heating!

Thats probably exactly why its like that.

stevehead

Originally Posted by richardc1983

WATER TO AIR (not sure as havent got these)

Cardew wrote: »

Novel concept!!;)

But out there nonetheless
http://www.heatingandventilating.net/products/product.asp?id=31

richardc1983

OH yes they use things like lakes, streams as the heat source.

YOu could set it up in your water feature steve!

thechippy

stevehead wrote: »

Yeah, it is... what do you make of that Rich? Why not the same for both heat/cool?

....Because, in heating mode the input energy to the compressor, along with it's naturally generated heat is also passed to the indoor unit via the condenser...;)

If comparing an ashp to an A rated condensing boiler, the break even point is about -3c, or a cop of around 2.3. So, if your cop is less than 2.3 or the outside temp is less than -3, an A rated condensing boiler starts to be the cheaper to heat the home.

richardc1983

thechippy wrote: »

....Because, in heating mode the input energy to the compressor, along with it's naturally generated heat is also passed to the indoor unit via the condenser...;)

If comparing an ashp to an A rated condensing boiler, the break even point is about -3c, or a cop of around 2.3. So, if your cop is less than 2.3 or the outside temp is less than -3, an A rated condensing boiler starts to be the cheaper to heat the home.

Yeh but steves system is lower rated in cooling but provides more heat than my unit that is rated at 3.5kw in heating!!!

Its almost twice as efficient as mine!

richardc1983

thechippy wrote: »

....Because, in heating mode the input energy to the compressor, along with it's naturally generated heat is also passed to the indoor unit via the condenser...;)
quote]

ALso my unit being a multi split produces excess heat so if the bedroom unit is thermostat off the fan still cycles on sometimes to clear the coil of heat.

This in turn heats the room up without even having to set up a temperature. Its fantastic!

mech_2

thechippy wrote: »

....Because, in heating mode the input energy to the compressor, along with it's naturally generated heat is also passed to the indoor unit via the condenser...;)

If comparing an ashp to an A rated condensing boiler, the break even point is about -3c, or a cop of around 2.3. So, if your cop is less than 2.3 or the outside temp is less than -3, an A rated condensing boiler starts to be the cheaper to heat the home.

I think 2.3 is the carbon emission break-even point, not the running cost break-even point. Not sure where -3 degrees comes into it unless you get a COP of 2.3 at -3 degrees.

My electricity costs just over 3 times as much per unit as my gas. 3 times 90% (minimum A rated boiler efficiency) gives a COP of 2.7 (ignoring DHW provision).